Rapid warming above air temp inversion elevation in Negro Canyon.

Location Name: 
Negro Canyon
Region: 
Donner Summit Area
Date and time of observation: 
Sun, 01/29/2017 - 10:00
Location Map: 
United States
39° 20' 44.3652" N, 120° 18' 26.622" W
See map: Google Maps
US


Red Flags: 
Rapid warming
Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

The difference in air temperatures and surface snow conditions above vs below the air temperature inversion layer set up between 6,600' to 7,200' in the area was very noticeable this morning. Below the air temperature inversion layer, very limited snow surface melt was occurring on solar aspects (E-SE-S-SW-W) at noon. Above the inversion layer, air temps well into the 50s had rapid surface melt occurring by 9 am. Dripping cornices and minor amounts of human triggered roller balls were observed by 10 am.

Wind scoured surfaces existed above treeline. Large cornices existed in the area along near treeline and above treeline ridgelines. No signs of any wind slab avalanche problem observed.

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
Clear
Air temperature: 
Below Freezing
Wind Speed: 
Calm
Air temperature trend: 
Warming